Heat exchanger design using HYSYS 1

[Abiodun1]

Hi guys,

how do i use HYSYS to specify a heat exchanger to increase the temperature of a process gas to desired temperature.

What is the effect of pressure drop in the hot stream.

Regards

 

[Montemayor]

Abio:

I understand from your query that you want us to show you how to use HYSYS in specifying a heat exchanger.

HYSYS is a Simulation Program. I specifically said this in a prior thread you posted. That means that HYSYS is not meant nor designed to "specify" equipment. It may help in designing equipment. It is primarily intended to simulate processes. If you don't know how to use HYSYS or haven't been trained in its use, then you should start with the basic understanding of what it is and what it can do for you. Then, if interested, start getting training in it. If you own (or have access to) such an expensive program, you surely can afford its training courses and seminars.

If you don't own HYSYS (or don't have access to a legal version) or you are a student seeking help in training, then you really have no business getting involved in it.

 

[frogcurry]

Effects of pressure drop depend on whats in the tubes and conditions...

If you want to use a program to design heat exchangers use HTFS-TASC. Or buy a book.

 

[Abiodun1]

Montemayor,

i think you are the one that do not understand my post. i know that i cant use HYSYS to do mechanical sizing, but it can perform the process simulations that you said.

actually, i was working on a model, ion which i tried to study the effect of pressure drop in the hot stream though the heat exchanger.

Frogcurry, understand the view i was coming from and it corresponds with the result i observed.

i underwent training in HYSYS and know how to use it.

thanks

 

[MortenA]

there are basically two HX trypes in HYSYS:

1) Heater/cooler : Simple model where transfer area, and utility side etc is unaccounted for

2) More rigerous model where both sides must be specified. The UA can be specified with more or less accuracy.

using 1) you will simply specify either the exchanger duty - the outlet temperature will then be calculated - or you will specify the outlettemperature and the duty will be calculated. The duty is specified in the cooler/heater and the temperature in the outlet stream. You can either specify a fixed pressuredrop (in the HX unit module) or an outlet pressure (in the outlet pressure). Either MUST be specified - and BOTH CANNOT.

Using 2) you must have both the hot and the cold stream defined before setting the HX up. You specify ether an outlet pressure or a pressure drop and you specify a UA. In the simplest case you simply specify UA - both more options are avaiable. Then HYSYS calculates the exchanged duty and the resulting in/out temperatures. Temperatures crosses etc can occur but warnings will be issued.

This is a rather quick introduction and if you are uncertain i must recommend training.

Best regards

Morten